diff --git a/plugins/xslt-debugger/engine/impl/src/org/intellij/plugins/xsltDebugger/rt/engine/local/saxon9/Saxon9Support.java b/plugins/xslt-debugger/engine/impl/src/org/intellij/plugins/xsltDebugger/rt/engine/local/saxon9/Saxon9Support.java
index 43fc5d331962..f531d7e312cd 100644
--- a/plugins/xslt-debugger/engine/impl/src/org/intellij/plugins/xsltDebugger/rt/engine/local/saxon9/Saxon9Support.java
+++ b/plugins/xslt-debugger/engine/impl/src/org/intellij/plugins/xsltDebugger/rt/engine/local/saxon9/Saxon9Support.java
@@ -67,7 +67,11 @@ public class Saxon9Support {
   public static TransformerFactory createTransformerFactory() {
     final TransformerFactoryImpl factory = new TransformerFactoryImpl();
     factory.setAttribute(FeatureKeys.TRACE_LISTENER, new Saxon9TraceListener());
-    factory.setAttribute(FeatureKeys.OPTIMIZATION_LEVEL, 0);
+    try {
+      factory.setAttribute(FeatureKeys.OPTIMIZATION_LEVEL, "0");
+    } catch (IllegalArgumentException e) {
+      e.printStackTrace();
+    }
     return factory;
   }
 }
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